Valve for rock drills



Oct.. A9, 192s. 1,687,381

G. M. NELL VALVE FOR Rock DRILLs Filed Sept. 24, 1923 Cit LPatented Oct. 9, 192,8.` 4 y jUNITED, STATES PATENT( oF y t CLEVELAND Rock ADRILL .coMrANx oF CLEVELAND, oHro. n

- 1,687,381 F1 ce.

l. Avanne: FOR Boex DiziILLs.v i

`Applicationfiled September 24, 1923. Serial No. 664,458.vv

The present invention is .directed to im provenients in vfluid distribul rock drills or the like. n

The invention has for its primary object to provide a valve of this nature so constructed that the port areas are increased without inf creasing ythe diameter of the vvalvel chest,

' whereby the valve chest will be comparatively light. s y

A further object of the invention is to provide avalve oft-his character which is extremely compact and light so as to gainhigh.

. speed vin operation.

formed acentrally located annular groove 6v With these and other objects in view this in if' vention resides in the novel features ofA construction, formation, combination and' ar- 'rancrement of arts to be hereinaftermore fully described, claimed and illustrated in the accompanying drawing, in which Figure 1 is a somewhat sectional'diagrammatic view showing the piston in `its forward or striking position and thevalve in a position to effect the rearward movement of the piston.

Figure 2 is a similar view showing the valve in its position to distribute'the -iiuid tol move the piston in a reverse direction. v ,Y

Referring to the present embodiment of the invention 1 designates the cylinder which has reciprocally mounted lin its chamber 2 the piston 3. The cylinder has associated there? witha transversely disposed valve chest 4 having a longitudinal bore 5. in which is which is in communication with the live Vair supply port 7, and upon opposite sides'of said groove are annular grooves Sand 9 and from which lead exhaust ports 10 and v11, respectively. Leading from the frontand rear' ends of the chamber 2 are combined fluid distributing-and exhaust permitting passages 12 and 13, which open into the bore 5 between ythe central groove 6 and grooves 8 and 9.

Extending axially through the bore 5 is a valve guide rod 14, one end thereof having a head 15 which closes theadjacent end of the bore, said head being provided Vwith an annular portion 15 and a reduced extension 16. The opposite end of the rod 14 is threaded as at 17 and extends beyond the chest 4. Removably engaged with the rod is an annular extension 18 having a terminal cup-shaped head 19, there being a rubber gasket 20 engagedv on the threaded end of the rod and located in the cavity of the head 19, a nut 21 being threaded upon said rod and engaged with the gasket lting valves for and serving to hold the rod against longitudinal movement. The gasket also serves tok ab-v sorb shocksincident to the valve 22 .striking the heads 15 and 19. To preventfrotation of sleeves 23 integrally connected by a collar 24,

which is restricted for slidably engaging the f rod 14, the internal diameters ofthe sleeves 23 being such as toy be annularly spaced from the r0d14 and capable of snugly andslidably receivingv the respective extensions 16 and 18, as clearly shown in Fig. lof the drawing.

The head 19 and |annular"portion 15y are surrounded by annular chambers 25 and 2G,l

v respectively. Passageways 27 and 28connect respectively intermediate portionsmof the chamber 2 Withthe'chambers 25 andv 26, and

since these chambers open into the chamber 2 they will be,alternatelycovered anduncovered asthe piston 3 reciprocates in the cham-y ber 2, whichaction permits motive fluidv from the chamber 2 toalternately enterY the end chambers 25jand 26 and act upon the end l ilanges 29fofthe valve 22; In addition to the end flanges 29, each sleeve 23 of the valve is provided with a pair of spaced annular webs from the ends of the chamber 2, through the passages 12 and 13 to alternately pass through the exhaust ports 10 to atmosphere, t-he passages 12and 13 ermitting fluid under pressure to alternate y enter the opposite ends of 30 and 31, the webs of `each pairbeing divergthe chamber 2 to reciprocate the piston 3.

Connecting the chambers 25 and 26 with the exhaust ports 10 areducts 35, and since the cross sectional area thereof is less than that of the portslO suicient pressure will be built up in the respective chambers 25 and 26 to shift V the valve before passing through the ports 10 and to atmosphere. It will be observed that the Webs 30 kwill prevent live air from passing from the grooves 8 and 9 to the exhaust ports 10, as will the webs 31 prevent live air from entering the respectivepassages 12 and 13, when serving as exhaust ports.

imy

" chestV `being wWhen the valve is in the position as shown in Fig. 1 of the di'awing,fliiid under pressure will pass from the port 7 and enter the groove 33 and from thence into the 'passage 13y and into the front end oi the'chainber 2, and will drive the piston 3 rearwardly, the exhaust `fluid having passed tl'irough the passage 12, groove 32 and exhaust port 10 upon the lett hand side of the valve. As the piston inoves rearwardly a small amount of luid conipressed in the chamber rearwardly oi' the piston will pass through the passageway 28 into the chamber 26 owing to the iact that the ad- ]acent duct 85 is relatively small. When a slight pressure is built up in said chamber itv Y will act upon the flange 29 and hold the valve momentarily in the positionas shown in Fig. 1.' This fluid bleeds to atii'iosphere 'through the associated duct 35 andrelieves the pres' sure in the chamber 26. iis soon as the piston uncoversthe passageway 27, upon its rearward movement, motivo fluid will pass yfrom the chamber 2 thereinto and enter the chainber 25, thereby moving the valve to the right to the position as shown in Fig; 2 ofthe drawing, whereupon live air willV enter the `rear end of the chamber 2, through the passage 12 and drive the piston 1l'orwardly, a small amount o-air under compression having entered the passageway 27 enters the chamber 25 and vholds the valve momentarily until the fluid bleeds to atmosphere through the associated duct 35. A

l lt will be observed that live air from the port 7 willat all times be in the groove and ready for distribution tothe respective passages 12 and 13, and the grooves 32 will be, alternatelyA brought into communication therewith iior distributing and exhausting the,V

fluid from theends oil-the piston chamber 2. What is claiinedise- 4 y 1.*The combination with a cylinder, oa

piston mounted therein, a valve chest ilorthe cylinder, a rod'ifixed axially iii the chest, said connected' with the cylinder y to and 'from the cylinder, said valve includingV a collarpandend sleeves, said sleeves being each provided with a plurality of diverging webs defining annular end grooves and a central groove Yfor controlling the distribution o fluid 'to and'li'omthecylinder through the distributing and exhaust ports, said valve also having end flanges, said chest having pressui'e chambers at each end, and means controlled by the piston or admitting"luidjun-V der pressure alternately to the pressure cham bers andagainst the `langes, and lineansif'ori exhaustinglluid from said chambers.

2. The combinationwith afcylindenjota piston mounted -tor reciprocation'therein, a, valve chest, fluid distributing and, exhaust" ports connecting the ends of the cylinder-with they valve chest, said chest havingjheads in its ends and surrounded by pressure chambers,' a rod connecting the heads, afvalve includingia' central collar for slidably engaging therod, and yend sleeves, said sleeves beingeachpr vided with a pair of spaced-annular webs"A the innermost webs defining therebetween a central grooveaiid (3o-operating with` the out# er webs to deline'end grooves, the central; groove being constantlyrincommunication with a source oflive ionith'e'chest'to' maintain a constant supply'oipressurelluid therein, said end grooves' b'eingfadaptedto control the distributionv and exhaust offno-l tive fluid to aiid'iirom thel cylinder' tl'irouglr the iiuid distributing "and" exhaust ports, 'flanges carried by, the ends ,of they sleeves and movable in the pressure chambers, and means4 controlled bythe piston 'for admittingfluid under pressure to "the pressure chambers against saidilanges to effect 'thereciproca-l tion oi' the valve.` y Y In testimonyv whereof I have" hereunto set" my hand.v

oUsTAvn M; Nenn 

